We are requesting funds to support a recently constituted Inner Ear Core Consortium designed to enhance exiting research programs and to promote cooperative interactions among 18 scientists at Central institute for the Deaf (CID), Washington University Medical School (WUMS), and St. Louis University (SLU). This consortium consists of an administrative Core Center, three research-oriented core facilities (Digital Imaging Core Electron Microscopy Core, and Gene Expression Core), and one service-oriented core facility (Electronic Services Core). These core facilities are physically located in a new CID research building, recently completed and occupied, immediately adjacent to the south end of the WUMS campus. The scientists in the Inner Ear Consortium have research backgrounds in anatomy, biochemistry, cell biology, developmental biology, molecular biology, molecular genetics, and physiology. These scientists have primary appointments in the Fay and Carl Simons Center for Biology of Hearing and Deafness, one of two centers of excellence at CID, the Departments of Otolaryngology, Anatomy and Neurobiology, Anesthesiology, Molecular Biology and Pharmacology at WUMS, and the Department of Anatomy and Neurobiology at SLU. The research programs of these scientists address crucial issues in the development, function, and regeneration of sensory receptors and their neuronal innervation in the vertebrate inner ear. The Inner Ear Consortium maintains expensive common equipment, supports the common needs of inner ear scientists for digital imaging, ultrastructural analysis, and studies of gene expression. It encourages research collaborations that cross existing research programs by promoting interactions among (1) researchers who study the morphology and physiology of the normal, developing, and regenerating inner ear, (2) researchers who study the inner ear on systemic, cellular, and subcellular levels, and (3) researchers who study the auditory and vestibular systems. It promotes the use of mutant and transgenic animal models and trains inner ear scientists in new research techniques, fostering the transfer of these techniques among inner ear laboratories. The Inner Ear Consortium also provides limited assistance for pilot projects, especially those that advance existing scientific programs, involve multiple investigators, or promise to provide new techniques of general interest to inner ear scientists. Finally, it enhances the research training that consortium members provide to residents and medical students in the Department of Otolaryngology and graduate students in the Departments of Speech and Hearing Sciences at CID and the Division of Biology and Biological Sciences at WUMS.